METHOD AND APPARATUS FOR DRUG INFUSION

• US 20010031947A1
• Filed: 10/11/1999
• Published: 10/18/2001
• Est. Priority Date: 04/30/1996
• Status: Active Grant

• Current Assignee: Eric R. Waldkoetter
• Original Assignee: Eric R. Waldkoetter
• Inventors: HERUTH, KENNETH T.
• Granted Patent: US 6,394,981 B2
• Time in Patent Office: Days
• US Class Current: 604/142
• CPC Class Codes: A61M 2005/14506 mechanically driven, e.g. spring or clockwork
• CPC Class Codes: A61M 2005/14513 with secondary fluid driving or regulating the infusion
• CPC Class Codes: A61M 5/14276 specially adapted for implantation

Abstract

The present disclosure describes a system wherein a drug or other fluid to be delivered to a specific desired location within the body is stored in a reservoir that is directly displaced by a force to infuse the drug from the device into the patient. Several specific methods are used to displace the reservoir, including, generally, hydraulic displacement, mechanical screw-type displacement, and spring force displacement of the fluid reservoir.

Claims

1. A drug infusion device, comprising:

a fluid reservoir; and

fluid reservoir displacement means for directly forcing drug fluid within said fluid reservoir from said device.

2. The apparatus of

claim 1

, wherein said fluid reservoir displacement means comprises hydraulic displacement means.

3. The apparatus of

claim 2

, wherein said hydraulic displacement means comprises a pump which circulates a working fluid between a first reservoir and an expandable second reservoir disposed proximate said fluid reservoir, so that as said second reservoir expands, said fluid reservoir is displaced.

4. The apparatus of

claim 2

, wherein said hydraulic displacement means comprises a piston assembly which acts to directly displace said fluid reservoir.

5. The apparatus of

claim 1

, wherein said fluid reservoir displacement means comprises mechanical screw-type displacement means.

6. The apparatus of

claim 5

, wherein said mechanical screw-type displacement means comprises a motor operatively coupled to a lead screw, so that as the motor turns the lead screw about a central axis, a nut coupled to said fluid reservoir and disposed on said lead screw is displaced along said central axis, displacing said fluid reservoir.

7. The apparatus of

claim 5

, wherein said mechanical screw-type displacement means comprises a motor that rotates a worm gear to displace a rack coupled to the fluid reservoir, displacing said fluid reservoir.

8. The apparatus of

claim 1

, wherein said fluid reservoir displacement means comprises spring force displacement means.

9. The apparatus of

claim 8

, wherein the spring force displacement means comprises a bellows-like expandable chamber annealed so that the chamber in its natural state assumes a collapsed position, and in an expanded state the chamber tends toward its natural collapsed position under its own action.

10. The apparatus of

claim 9

, wherein said spring force displacement means further comprises a motor assembly, including a motor operatively coupled to a flywheel about which a first end of a cable having first and second ends is wrapped, said second end of said cable being attached to said bellows-like expandable chamber and wherein said motor assembly adjusts the position of the bellows-like expandable chamber as it relaxes from a first expanded state to a second more collapsed state to control the displacement of the fluid reservoir.

11. A drug infusion device, comprising:

a fluid reservoir; and

fluid reservoir displacement means for directly drawing drug fluid into said fluid reservoir.

12. The apparatus of

claim 11

, wherein said fluid reservoir displacement means comprises hydraulic displacement means.

13. The apparatus of

claim 12

, wherein said hydraulic displacement means comprises a pump which circulates a working fluid between a first reservoir and a contractible second reservoir disposed proximate said fluid reservoir, so that as said second reservoir contracts, said fluid reservoir is displaced.

14. The apparatus of

claim 12

, wherein said hydraulic displacement means comprises a piston assembly which acts to directly displace said fluid reservoir.

15. The apparatus of

claim 11

, wherein said fluid reservoir displacement means comprises mechanical screw-type displacement means.

16. The apparatus of

claim 15

, wherein said mechanical screw-type displacement means comprises a motor operatively coupled to a lead screw, so that as the motor turns the lead screw about a central axis, a nut coupled to said fluid reservoir and disposed on said lead screw is displaced along said central axis, displacing said fluid reservoir.

17. The apparatus of

claim 15

, wherein said mechanical screw-type displacement means comprises a motor that rotates a worm gear to displace a rack coupled to the fluid reservoir, displacing said fluid reservoir.

18. The apparatus of

claim 11

, wherein said fluid reservoir displacement means comprises spring force displacement means.

19. The apparatus of

claim 18

, wherein, the spring force displacement means comprises a bellows-like expandable chamber annealed so that the chamber in its natural state assumes a collapsed position, and in an expanded state the chamber tends toward its natural collapsed position under its own action.

20. The apparatus of

claim 19

, wherein said spring force displacement means further comprises a motor assembly, including a motor operatively coupled to a flywheel about which a first end of a cable having first and second ends is wrapped, said second end of said cable being attached to said bellows-like expandable chamber;

and wherein said motor assembly adjusts the position of the bellows-like expandable chamber from a first contracted state to a second more expanded state to displace the fluid reservoir.

21. A method of infusing a drug to a specific desired location within a patient'"'"'s body, comprising:

placing a measure of the drug within a fluid reservoir and forcing at least a portion of the drug from the fluid reservoir and through an established fluid passageway extending between the fluid reservoir and the specific desired location within the patient'"'"'s body by directly displacing said fluid reservoir.

22. A method of filling a drug reservoir in an implantable drug infusion device, comprising:

providing a supply of fluid; and

directly displacing said fluid reservoir to draw at least a portion of the provided supply of fluid into said fluid reservoir.